The man responsible for the mass killing in Norway emailed his 1,500-page document to 250 British contacts less than 90 minutes before he began his attack, according to a Belgian MP.

Anders Behring Breivik sent his manifesto to 1,003 email addresses at 2.09pm on Friday – less than an hour and a half before he detonated a bomb in Oslo.

According to Tanguy Veys MP for the rightwing anti-Muslim party Vlaams Belang, – and one of those who received the document – approximately a quarter of those on the email list were UK-based.

"I think the UK was the biggest group [of recipients]," he told the Guardian last night. "There were people from Italy, France Germany … but the UK was the biggest number."

Using the name Andrew Berwick, Breivik emailed his manifesto and a link to a YouTube video and addressed each recipient "Western Europe patriot" and wrote: "It is a gift to you … I ask you to distribute it to everyone you know."

It has been reported that Scotland Yard's domestic extremism unit, which is investigating Breivik's British links, has been sent a list of UK-based email addresses although the Met refused to confirm that.

Veys said he had not had any contact with Breivik and condemned his actions.

"Looking through this it seems very difficult to find a criteria for who he sent it to … it is very strange and I am cross I have been associated with him in any way."

The news of the emails came as anti-racism campaigners in the UK said they believed Breivik may have been in touch with activists from the far-right English Defence League as recently as March.

Searchlight, the anti-fascist magazine, said the 32-year-old used the pseudonym of a 12th-century Norwegian king who led one of the Crusades to communicate with people on an English Defence League forum.

In one posting, on 9 March, the author called on rightwing activists in the UK to "keep up the good work". The message said: "Hello. To you all good English men and women, just wanted to say that you're a blessing to all in Europe, in these dark times all of Europe are looking to you in such [sic] of inspiration, courage and even hope that we might turn this evil trend with islamisation all across our continent. Well, just wanted to say keep up the good work it's good to see others that care about their country and heritage. All the best to you all. Sigurd."

Breivik boasted about his links to the UK far-right group in his manifesto. He also wrote that he was given the codename "Sigurd (the Crusader)" at a founding meeting of a group called the Knights Templar Europe in London in 2002. There is no confirmation that the author is Breivik. Sigurd is a common name in Norway.

In other messages, "Sigurd" says he attended a football ground in the UK and expressed his admiration for the EDL.

"I've seen with my own eyes what has happened to england, i was in bradford some years ago, me and a friend walked down to the football stadium of bradford, real 'nice' neighborhood, same thing in the suburbs of london. well thinking about taking a little trip over the sea and join you in a demo. would be nice with a norwegian flag alongside with union jack or the english flag, that is if a norwegian would be welcome offcourse?"

In another message, he goes on to discuss the situation in Norway.

"The biggest problem in Norway is that there is no real free press, there is a left-wing angle on all the political topics so most people are going around like idiots. And offcourse with our norwegian labour party beeing in power for most of the last 50 years dont help. but i i think there is an awakening now at least i hope so."

In his manifesto, Breivik repeatedly refers to the EDL, stating at one point: "I used to have more than 600 EDL members as Facebook friends and have spoken with tens of EDL members and leaders."

"In fact, I was one of the individuals who supplied them with processed ideological material (including rhetorical strategies) in the very beginning."

"There also appears to be a growing dispute among some figures associated with the EDL over who Breivik's "mentor" Richard may be. In his manifesto, the Norwegian said he met "Richard" at the Knights Templar meeting in 2002 and says the pair became "close."

The EDL – which has staged a series of street demonstrations, many of which have turned violent, denies any links to Breivik and has condemned the killings, stating it is a peaceful organisation that rejects all forms of extremism.

Last night the EDL said in an emailed statement that it was "not aware of any contact between Breivik and EDL leadership … of anyone using the name Sigurd and the forum".

"You must realise anyone on the EDL Forum or EDL Facebook can join and make up any name that they may choose."

Since the killings there have been unconfirmed reports that Breivik attended EDL demonstrations in the UK last year – possibly in London and Newcastle

A surveillance camera in a technology store in Oslo catches the moment the bomb blast strikes, while police detonate a cache of explosives at a farm rented by Anders Behring Breivik, the man charged with carrying out the attacks